I thought the talking was to avoid spooking them, to let them know where you are, like talking to horses, or making noises in the presence of gorillas?
Most aren't, in my experience. Sales of ale would plummet if it wasn't for scientists! But he didn't seem to be doing much science, and a look round his website suggests it's more about 'adventure' and 'outreach'. To quote:
"Chris' Mission
To make conservation a social norm.
Chris Morgan is a conservation ecologist who works through education, film, science, and campaigns to highlight wildlife conservation in fresh, fascinating ways."
A quick look on Google Scholar failed to turn up any scientific research papers in his name. He sounds like more of an 'activist/publicist' than a 'scientist'. Nothing wrong with that, but I'm not sure we should categorise what he was doing on the television as 'science'. It was entertainment/awareness, and I actually cannot think of a significant difference between that and what Timothy Treadwell was doing. The mission statement sounds eerily similar.